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Title: Sputtering at grazing ion incidence: Influence of adatom islands

Abstract

When energetic ions impinge at grazing incidence onto an atomically flat terrace, they will not sputter. However, when adatom islands (containing N atoms) are deposited on the surface, they induce sputtering. We investigate this effect for the specific case of 83 deg. -incident 5 keV Ar ions on a Pt (111) surface by means of molecular-dynamics simulation and experiment. We find that - for constant coverage {Theta} - the sputter yield has a maximum at island sizes of N congruent with 10-20. A detailed picture explaining the decline of the sputter yield toward larger and smaller island sizes is worked out. Our simulation results are compared with dedicated sputtering experiments, in which a coverage of {Theta}=0.09 of Pt adatoms are deposited onto the Pt (111) surface and form islands with a broad distribution around a most probable size of N congruent with 20.

Authors:
 [1];  [2]; ;  [3];  [1]
  1. Fachbereich Physik und Forschungszentrum OPTIMAS, Universitaet Kaiserslautern, Erwin-Schroedinger-Strasse, D-67663 Kaiserslautern (Germany)
  2. (Indonesia)
  3. II. Physikalisches Institut, Universitaet Koeln, Zuelpicherstrasse 77, D-50937 Koeln (Germany)
Publication Date:
OSTI Identifier:
21421431
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 82; Journal Issue: 12; Other Information: DOI: 10.1103/PhysRevB.82.125440; (c) 2010 The American Physical Society
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ARGON IONS; ATOMIC CLUSTERS; ATOMS; CRYSTAL DEFECTS; DISTRIBUTION; ION-ATOM COLLISIONS; KEV RANGE 01-10; MOLECULAR DYNAMICS METHOD; PLATINUM; SIMULATION; SPUTTERING; SURFACES; TAIL IONS; ATOM COLLISIONS; CALCULATION METHODS; CHARGED PARTICLES; COLLISIONS; CRYSTAL STRUCTURE; ELEMENTS; ENERGY RANGE; ION COLLISIONS; IONS; KEV RANGE; METALS; PLATINUM METALS; TRANSITION ELEMENTS

Citation Formats

Rosandi, Yudi, Department of Physics, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Redinger, Alex, Michely, Thomas, and Urbassek, Herbert M. Sputtering at grazing ion incidence: Influence of adatom islands. United States: N. p., 2010. Web. doi:10.1103/PHYSREVB.82.125440.
Rosandi, Yudi, Department of Physics, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Redinger, Alex, Michely, Thomas, & Urbassek, Herbert M. Sputtering at grazing ion incidence: Influence of adatom islands. United States. doi:10.1103/PHYSREVB.82.125440.
Rosandi, Yudi, Department of Physics, Universitas Padjadjaran, Jatinangor, Sumedang 45363, Redinger, Alex, Michely, Thomas, and Urbassek, Herbert M. 2010. "Sputtering at grazing ion incidence: Influence of adatom islands". United States. doi:10.1103/PHYSREVB.82.125440.
@article{osti_21421431,
title = {Sputtering at grazing ion incidence: Influence of adatom islands},
author = {Rosandi, Yudi and Department of Physics, Universitas Padjadjaran, Jatinangor, Sumedang 45363 and Redinger, Alex and Michely, Thomas and Urbassek, Herbert M.},
abstractNote = {When energetic ions impinge at grazing incidence onto an atomically flat terrace, they will not sputter. However, when adatom islands (containing N atoms) are deposited on the surface, they induce sputtering. We investigate this effect for the specific case of 83 deg. -incident 5 keV Ar ions on a Pt (111) surface by means of molecular-dynamics simulation and experiment. We find that - for constant coverage {Theta} - the sputter yield has a maximum at island sizes of N congruent with 10-20. A detailed picture explaining the decline of the sputter yield toward larger and smaller island sizes is worked out. Our simulation results are compared with dedicated sputtering experiments, in which a coverage of {Theta}=0.09 of Pt adatoms are deposited onto the Pt (111) surface and form islands with a broad distribution around a most probable size of N congruent with 20.},
doi = {10.1103/PHYSREVB.82.125440},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 12,
volume = 82,
place = {United States},
year = 2010,
month = 9
}
  • Grazing incidence small-angle x-ray scattering and grazing incidence x-ray diffraction from SiGe nanoscale islands grown on Si(001) substrate were investigated. Experiments and corresponding theoretical simulations based on the distorted-wave Born approximation were carried out. The strain field inside and in the vicinity of the SiGe islands was calculated in the framework of linear elasticity theory using the numerical finite element method. The diffuse intensity pattern in reciprocal space reveals a well-resolved fine structure with prominent maxima and a complicated fringe pattern. The distribution of diffuse intensity in reciprocal space strongly depends on the angle of incidence with respect to themore » sample surface. The results obtained substantiate the important role of basically five (grazing incidence small-angle x-ray) and nine (grazing incidence diffraction) scattering channels that have to be considered for a complete understanding of the scattering scenario. A refined island model concerning shape, size, and Ge composition was elaborated.« less
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